This invention relates to a turbine casing and is particularly concerned with the cooling of such a casing.
The turbine of a gas turbine engine typically comprises a circular cross-section casing which encloses axially alternate annular arrays of aerofoil blades and vanes. During the operation of the engine, hot gases exhausted from the engine combustion equipment are passed through the turbine in order to provide rotation of the annular arrays of turbine blades.